1. Field of the Invention
This invention relates to a controlling device for a headlamp's high and low beam, particularly to one provided with an electromagnetic valve having its valve rod driving a light-obstructing plate to turn and shift for controlling a light projecting range of a headlamp and carrying out change-over of high and low beam of the headlamp.
2. Description of the Prior Art
An automobile is generally provided with a change-over device for controlling high and low beam of a headlamp by turning a whole headlamp holder to different angles. However, the conventional way to turning the whole headlamp holder to adjust a headlamp's high and low beam may damage electric wires and shorten the service life of the headlamp. In view of the situation, a device provided with an electromagnetic valve to drive a light-obstructing plate for controlling a headlamp's high and low beam is devised. This conventional control device 1, as shown in FIGS. 1-4, is assembled between the lamp holder 10 of a lamp 100 and a transparent lamp shade 101, composed of a fixing plate 11, a valve seat 12, a light-obstructing plate 13, an elastic retainer 14, a pull plate 15 and a backing plate 16. The fixing plate 11 to be transversely fixed on the lamp holder 10 is disposed with a notch 110 at a location corresponding with the lamp 100 and formed thereon with two opposite protruding pivotal seats 111 and bored with a plurality of combining holes 112. The valve seat 12 to be threadably assembled at one side wall of the fixing plate 11 is installed in the interior with an electromagnetic valve 120 with a valve rod 121 having its upper end cut with an annular groove 122 with a spring 123 fitted around it. The light-obstructing plate 13 is pivotally assembled at one side of the fixing plate 11 and positioned on the valve seat 12, having its opposite ends respectively formed with a pivotal projection 130 bored with an upper pivotal hole 131 and a lower pivotal hole 132. The elastic retainer 14 has two ends respectively inserted in the two opposite lower pivotal holes 132 of the pivotal projection 130 and closely rests against the wall surface of the fixing plate 11. The pull plate 15 has two ends respectively inserted in the opposite two upper pivotal holes 131 of the light-obstructing plate 13, disposed with a fitting groove 150 to be engaged with the annular groove 122 of the valve rod 121 of the electromagnetic valve 120 to let the pull plate 15 press the upper end of the spring 123. The backing plate 16 is threadably mounted at another side of the fixing plate 11 and bored with insert holes 160 respectively corresponding with the combining holes 112 of the fixing plate 11. Thus, when actuated to extend and contract, the valve rod 121 of the electromagnetic valve 120 will drive the pull plate 15 to shift downward and actuate the light-obstructing plate 13 to move bias for controlling the size of a light projecting area and carrying out change-over of a headlamp's high and low beam. Nevertheless, the conventional control device of a headlamp's high and low beam is provided with numerous members, requiring a lot of time and trouble in assembly and increasing manufacturing cost.
At present, using an electromagnetic valve to drive a light-obstructing plate to change its position for regulating a light projecting area is a design tendency of controlling a headlamp's high and low beam.
Based on this conception, the inventor of this invention devised a new device for controlling a headlamp's high and low beam, able to improve the drawback of the conventional device, simplify members, elevate assembly efficiency and lower cost.